[PATCH] drm/ttm: Don't evict BOs outside of the requested placement range

[Daniel Vetter]

On Fri, Oct 10, 2014 at 05:59:19PM +0900, Michel Dänzer wrote:
> On 10.10.2014 17:51, Alan Swanson wrote:
> >On Fri, 2014-10-10 at 12:20 +0900, Michel Dänzer wrote:
> >>On 09.10.2014 19:22, Alan Swanson wrote:
> >>>On 2014-10-09 07:02, Michel Dänzer wrote:
> >>>>From: Michel Dänzer <michel.daenzer at amd.com>
> >>>>
> >>>>The radeon driver uses placement range restrictions for several reasons,
> >>>>in particular to make sure BOs in VRAM can be accessed by the CPU, e.g.
> >>>>during a page fault.
> >>>>
> >>>>Without this change, TTM could evict other BOs while trying to satisfy
> >>>>the requested placement, even if the evicted BOs were outside of the
> >>>>requested placement range. Doing so didn't free up any space in the
> >>>>requested placement range, so the (potentially high) eviction cost was
> >>>>incurred for no benefit.
> >>>>
> >>>>Nominating for stable because radeon driver changes in 3.17 made this
> >>>>much more noticeable than before.
> >>>>
> >>>>Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=84662
> >>>>Cc: stable at vger.kernel.org
> >>>>Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
> >>>>---
> >>>>  drivers/gpu/drm/ttm/ttm_bo.c | 20 +++++++++++++++++---
> >>>>  1 file changed, 17 insertions(+), 3 deletions(-)
> >>>>
> >>[...]
> >>
> >>>I believe you need to "s/place/placement/" over this patch.
> >>
> >>The fpfn and lpfn members were moved from struct ttm_placement to a new
> >>struct ttm_place in f1217ed09f827e42a49ffa6a5aab672aa6f57a65.
> >>
> >>If you mean something else, please elaborate.
> >
> >This patch failed to build on 3.17.0 so wouldn't be a candidate for
> >stable unless the currently drm-next only ttm_place patch also goes to
> >stable (else replace ttm_place with ttm_placements in the patch for
> >stable)?
> 
> Right, I guess I should drop the Cc: stable then and submit a manual
> backport of it to the stable list once it has landed in Linus' tree.

I've thought it's ok to cc: stable a patch - Greg's scripts will send you
a mail as a nice reminder if the patch fails to apply. At least we
regularly pull this stunt with i915 patches. Cc'ing Greg for
clarification.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch